The process of supercritical fluid extraction (SFE) comprises separating one component (i.e. the extractant) from another (i.e. the matrix) using supercritical fluids as the extracting solvent. A supercritical fluid comprises a substance at a temperature and pressure respectively above the critical temperature and the critical pressure, i.e. the critical point. In other words, a state where distinct liquid and gas phases do not exist.
A common supercritical fluid used in SFE is carbon dioxide (CO2). In essence, in CO2 SFE, the CO2 is used as a solvent for the matrix. In a typical CO2 SFE system, the SFE system includes an extractor receiving the matrix and supercritical CO2, and an evaporator producing the extractant and waste CO2. A typical drawback to earlier CO2 extraction systems was that they were largely stationary and bulky. Accordingly, extraction applications may require substantial investment into equipment and maintenance. Also, some agrarian applications may not be suitable for this type of permanent installation.